Blindstitch sewing-machine.



W. ARBETTBR. BLINDSTITOH SEWING MACHINE.

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APPLICATION FILED FEB.28, 1908.

Patented Apr. 29, 1913.

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W. ARBETTER. BLINDSTITCH SEWING MACHINE. APPLIOATION'IILBD FEB. 28, 1908.

L59 9 6., Patented Apr. 29, 1913.

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' nm'rnp srairns rarnnr omen WOLF RBETTER; or CHELSEA; MASSACHUSETTS, AssIeNon To ARBETTER FELLING MACHINE COMPANY, or BOSTON, MASSACHUSETTS, A CORPORATION or MAINE.

. BLINDSTITCH SEWING-MACHINE.

Specification of Letters Patent.

To all whom it may concern.

Be it known that I,"WOLF'ARBE'1'1ER, a citizen of the United States, and a resident of Chelsea, in the county of Suffolk and State of Massachusetts, have invented an Improvement in 'Blindstitch Sewing-Mm chines, of which the following .description,

in connection with the accompanying drawing, is a specification, like letters on the drawing representing like parts.

This invent-ion relates to a sewing machine for making blind stitches, and in that em-- bodiment of the'invention illustrated is-substantially of the general type shown in the granted September 11, 1906. q q

The present invention is designed to secure a machine particularly designed for felling work, or the attachment to a base layer of the edge of a superimposed layer or layers, and in so doing to imitate closely hand fellingwork wherein a series of substantially straight, parallel stitches extending a short distance from the top of the superimposed layer over the edge thereof and at right angles or slightly oblique thereto alone are visible.

The invention will more fully appear from the accompanying description and drawings and will be'particqlarly pointed out in the claims.

The drawings represent a sewing machine embodying the invention in its preferred form. -1

Figure 1 represents a front end elevation of the machine. Fig. 2 is a side elevation. Fig. 3 is a detail view to showthe operation of the needle vibrating cam. Fig. 4 is a diagrammatic view to show the operation of the bender driving cam and the irregular motion of the feed.

The general construction of the machine is similar to that of the machine shown in the patent above referred to and need not therefore be described in detail. The base A and the overhanging arm A? are of suitable construction to-support the operating parts. The main driving shaft A operated by a pulley A extends through the overhanging arm and from it the various mechanisms ,of'the machine are driven; the feeding and bender mechanism from the beveled gear D the needle vibrating mechanism from the pinion C the looper or rotating" hook mechanism from the beveled gear A; the needle reciprocating mechanism from the disk B. i

In the form of the machine shown a curved needle a is employed and is carried by an arm 6 mounted on a needle-carrying rock-shaft B, which extends through a bearing B which bearing is connected by the screw 10 to the block B connected to the vertically extending rock-shaft 13 The needle is given its reciprocations to form the stitch by the rocking ofthe shaft B This is secured by a rod 13 eccentrically connected at its upper end with the disk B already described, and its lower end with the rock-arm B I The needle is given a vibrating motion so that its paths of reciprocation may occur in different lines at the required times, and in the embodimentrshown this vibrating movement is secured by a bodily oscillation, of the needle from the vertical rock-shaft 13 The axis of the shaft 13 about which the needle oscillates in making its reciproca tions, is set in the rear of the axis of the rock-shaft B so that the shaft B moves bodily onthe arc of a circle about the ,vertical rock-shaft B The movement of the shaft B is secured in the form shownby the following means: A rotary face cam W is driven by the gear C thereon, intermesh- Anarm (9 extends from the rock-shaft B and carries the roller 0, which rides against the facecam C and is made adjustable on the ,arm-C to vary the extent of movement given to the shaft B by the face cam C A coiledspring holds the roll C up against the face cam and thus serves to move the shaft B? in the opposite direction-t0 the movement'given it by the cam. From the detailshown in Fig. 3 it will be observed that'the face cam W rellatented Apr. 29, 11913. Application filed February 28,1908. SerialNoi 418,181.

ing with the pinion C already described.

volves one-third as fast as the driving shaft A and is provided with a raised portion W covering about one-third of its surface. Consequently it will be seen that the needle makes three reciprocations for each revolution of the cam W, and hence one-of these reciprocations will occur while the needle is operating in one path due to the influence of the raised portion W and the other two will occur while the needle is operating in the other path under the influence of the low portion of the cam W. The adjustments are so arranged that the latter two reciprocations will take place in a straight line in the direction .of the feed of the machine, and hence the remaining reciprocation influenced by the raised portion W in the cam, will take place in a line diagonal thereto.

The complemental stitch-forming mechanism is shown'asa rotatinghook a with inclosed bobbin case and bobbin, operating in a plane'transverse and oblique to the paths of reciprocation of the needle in the line 01% the feed, and driven from the inclined shaft A by the beveled gear A intrmeshing with the beveled gear A already described. The hook is preferably arranged to make two rotations to each reciprocation of the needle,

:thereby enabling greater speed with the proper interlocking of the loops.

A suitable presser-foot, rigidly attached by its shank d to the presser-foot carrier d,

'adjustably supported from the overhanging arm, is provided and is of the general type shown in the said patent, being provided with means for guiding the edge, plain or, folded, ofa superimposed layer or layers of material with proper relation to the paths of the needle, and in such manner that when the needle makes its straight thrust it passes parallel and close to the said edge and into end out ,of the upper surface of the base ayer. A i

. The work su'pport E is mounted on a vertically-movable carriage E sliding in the ways E, and carrying the feeding device E slotted at its lower end to rock and slide on the stud E mounted on the carriage E. The feeding device is moved u wardly and forwardly by a cam D carrie by the shaft D ymounted in bearings in the carriage E, and is moved 'backwardly and downwardly by the spring E. t.

The bender G, by means of which the cloth when below the line of reciprocation of the needle is pushed up into the path thereof so as to enable the needle to enter and emerge therefrom and make a blind stitch therein, is mounted to slide vertically 1n the bearing G and operated by the bender The lever Gr receives its operation in one direction from the rotary cam S, a roll Gr on the end of the lever coopwerating therewith, and in the other direction from a spring M connected thereto and to the base A A 4 The required 0 eration of the feed and bender is secure as follows: A vertical shaft D, mounted in the arm A, is driven with a gear T mounted on a second and parallel stub-shaft T The relation of the plnlon Tand the gear T is that of one to intermeshing with a corresponding elliptic gear S, on the stub-shaft T,-and the cam S (already described) is mounted on the end of the stub-shaft T The cam S and the elliptic gears S S detail illustrated in'Fig. 4. The cam S is so shaped as illustrated that during one r0: tation thereofby the shaft T it will depress the bender twice, once for a sufficient period to enable the material to lie flat and undisturbed while the needle makesthe di-' agonal stitch into the superimposed layer or layers and once for a brief period while the feed takes place, and between these two depressions of the bender the cam acts twice to raise the bender and bring the material into the path of the needle in making its reciprocations to form the straight stitches.

The elliptic gears S, S are so arranged that the feed shaft D is driven at its maxi-- mum speed when the bender is depressed after the needle has left the fabric in completing a straight stitch and before it has entered the fabric to make the succeeding straight stitch to allow the feed taking place, and at its minimum speed during the reciprocation of the needle to form the diagonal stitch, and the vibrations of the needle occurring before and after said diagonal stitch. The cams D and S are made adjustable on their respective shafts by suitable means such as set screws, one of which is illustrated at S, so that the desired timing may readily be secured.- The position and their relations may best be seen in the p shown in Fig.- 4 has been found to work f very satisfactorily. Therein the feed cam Di is, for convenience, illustrated as on the same axis as the shaft D carrying the gear S In the position illustrated the feeding movement is shown as nearly com leted which will happen when the radial line 13 through the high point'14 of the cam D reaches the horizontal and the roll G is shown as just starting off the high part of the cam S to allow the bender to rise. The cycle of operations of the machine includes, therefore, three reciprocations of the needle and the order in which the machine pro-j ceeds is, therefore,'as follows: First, a reciprocation of the needle into and out of the fabric with the needle moving in a path determined by the flat surfage W of the face cam W the benden at that time being raised; second, a vibration of the needle into tion determined by the raised portion W of the face cam C and' hence as herein illustrated in adiagonal direction, the bender being depressed; fourth, a vibration of the needle back, into the former path of reciprocation; fifth, a reciprocation: of the needle into and out of the fabric with the '.near the edge,

interlocking point at the end of the straight needle moving in the former path of reciprocation determined'by the fiat surface W of the face cam C the bender at that time being raised; sixth, a quick feeding movement at high speed with the bender depressed. It .will thus be noted that two straight stitches are taken in the same place and that the cycle of three stitches, straight, diagonal, straight, is completed each time before the feed takes place.

The result of the operation. of the mechanism herein described will be that the thread will extend in short parallel lines from the points where the needle emerges from the upper surface of the, superimposed layer down over the edge to the stitches. The, tension, placed upon the thread will determine what. thread lies on the surface of the superimposed layer, but

, drawn under and needle,

it may readily be adjusted so'that only the looper thread will show on the upper surface of the material, while the interlocking points of the' thread at the'ends of the straight stitches being close up against the (edge of the superimposed layer will be thereby.

Having described my invention, what I claim as new and desire to secure by Letters Patent, is: I l

-1. In a blind stitch sewing machine having a cycle of operations including three'reciprocations of the needle, a reciprocating complemental stitch forming mech anism and operating mechanism therefor.

- means for vibrating the needle laterally be fore and after every third ,reciproeatio-n only, means for feeding the material, the sald feedmg means operating only after the reciprocation of the needle occurring after the second vibration.

2, In a blind-stitch sewing machine having a cycle of operations including three reciprocations of the needle, a reciprocating needle, complemental stitch-forming mechanism and operating mechanism therefor, means for vibrating the needle laterally before and after every third reciprocation, means for feeding the material after the reciprocation of the needle occurring after the second vibration, a bender to raise the material mto the path of the needle, and means practically concealed till erally before and'after every third recipro-- cation only, means for feeding the material after the reciprocation of the needle occur ring after the second vibration, and complemental stitch-forming mechanism including a rotating hook and inclosed bobbin, and means for operating said hook to make two rotations to each reciprocation of the needle.

4. In a'b'lind-stitch sewing machine having a cycle'of operations including three reciprocations of the needle, a reciprocating needle, complemental stitch-forming mechanism, and operating mechanism therefor, means for vibrating the needle laterally before and after every third reciprocation only, means for guiding the edge of'a superimposed layer parallel and close to the paths of reciprocation, whereby the said third reciprocation shall carry theneedle into or beneath said edge and out from the upper surface of said layer, and the other two reciprocations of each cycle shall carry'the needle into and out of the upper surface of the base layer close to and parallel with said edge, and means for feeding the material after the reciprocation of the needle occurring after the second vibration.

5. In a blind-stitch sewing machine hav ing a cycle of operations including three reciprocations of the needle, a reciprocating needle, complemental stitch-forming mechanism, and, operating mechanism therefor.

means forvibrating the needle laterally before and ,after every third reciprocation, means for guiding the edge of a superlmp'osedlayer parallel and close to the paths of reciprocation, whereby the said third reciprocation shall carry the needle mto or beneath said edge and out from the upper surface of said layer, and the other two reciprocations of each cycle shall carry the needleinto and parallel wit said upper surface of the base layer close to and parallel with said edge, and means for feeding the material after the reciprocation ofthe needle occurring after the second vibration, a bender to raise the material into the path of the needle,- and .means to raise said bender and maintain it raised during the first part of the-reciprocations of the needle into the base layer.-

6. In a blind-stitch sewing machine hava ing a cycle of operations including three reciprocations of the needle, a curved reciprocating needle, complemental thread-carryingstitch-forming mechanism and operating mechanism therefor, means for bodily swing- 'ing said needle laterally before and after every third reciprocation only, and meansfor feeding the material after the reciprocation of the needle occurring after the secnd vibration.

7. In a blind-stitch sewin machine having a cycle of operations inc uding three reciprocations of the needle, a curved reciprocating needle,- complemental thread-carrying stitch-formin ing mechanism t erefor, means for odily swinging said needle laterally before and ,7- after every third-reciprocation, means for feeding the material after the reciprocation of the needle occurring after the second vibration, means for guiding the edge of a superimcipcsed layer past the needle sothat the. nee le shall enter the folded edge diagonally in making one reciprocation, and

shall enter the base layer close to and parallel w1th said edge in making the receding and subsequent reciprocations, a ender to raise the material into the ath of the needle, and means to raise sa i bender and' maintain it raised during the'first' part of the reciprocations of the needle entering the base layer.

8. In a blind-stitch sewin machine having a cycle of operations inc uding three re-,

mechanism and o v erat-i ciprocations of ;the needle, a driving shaft a curved needle, connections between sai haft andsald needle for giving one com- ;plete I901 I'OOlltlOIlflf sald needle to each 11otat ioni-o said shaft, complemental stitch-v said shaft to give one feeding movement to each three rotations of the; said shaft, a bender, and connections between the same and the said shaft .togive two reciprocations' of the saidbender to each three rotations of the-said shaft.

In testimony whereof, I have signed :my name to this s ecification, in the presence of twosubscriblng witnesses.-

WOLF A-RB'ETTER.

Witnesses MABEL Pamnow, TnoMAs J. .DRUMMOND. 

